PARTS OF AN INSECT. 65 



CHAPTEE IX. 



PARTS OF AN INSECT (CONTINUED). 



62. The pupils have learned that the abdomen is divided 

 into rings or segments, and the division between these seg- 

 ments is plainly seen in most insects. 



The thorax is divided in a similar manner, only the lines 

 which divide the thorax are not so plainly seen. 



The number of segments in the thorax is three. To the 

 first segment, the head and first pair of legs are attached ; to 

 the second segment, the second pair of legs and the first pair 

 of wings are attached ; and to the third segment, the hind 

 pair of legs, the hind pair of wings, and the abdomen, are 

 attached. The three segments of the thorax have special 

 names : the pi-othorax, this being the forward segment, next 

 to the head; mesothorax, being the middle segment; and 

 metathorax, being the last segment. Arranging these seg- 

 ments with the appendages attached to them in a table, they 

 would appear as follows : 



The Thorax is com- 

 posed OF Three Seg- 

 ments. 



f Has attached to it the first pair of 

 1st Segment, Prothora^^ i igrrg. 



Has attached to it the second pair of 

 leg-s and the first pair of wings. 



Has attached to it the third pair of 

 legs and the second pair of wings. 



2d Segment, Mesothorax^ 

 8d Segment, Metathorax^ 



63. Let the pupils now endeavor to dissect a beetle, care- 

 fully separating the segments of the thorax, and, if possible, 

 the minxite jaws and other mouth-parts, and stick them on 



